European residents are better protected by law from privacy intrusions by unmanned aircraft than people on U.S. soil, but companies operating drones commercially or for law enforcement purposes need to be aware of the European privacy regulations, a lawyer specializing in technology said on Thursday.

While European countries are crafting laws to enable companies to use drones for commercial and law enforcement purposes, the operators of unmanned aircraft systems (UAS), more commonly known as drones, should take privacy issues seriously, said attorney Peter Lee. "We are a relatively new sector."

"We are silent and fly at altitude, that makes us practically invisible," he told the audience during his presentation at Eindhoven University of Technology. "We can hover over homes, see inside windows."

Lee urged the audience, which mainly consisted of people interested in operating some kind of UAS system, to take European privacy laws into account. Drones with camera equipment are especially likely to be subject to privacy and data protection laws, he warned. To avoid potential problems, the industry should set the privacy agenda itself, for instance by starting an E.U. lobby, he advised. If the issue is not addressed properly, there might by "rocky times ahead" for the drone industry in Europe.

Drones typically fly at a very low altitude, a maximum of a few hundred meters in the air. "That is close enough to recognize faces," Lee said. This means that companies have to get special permission if they want to process images and publish them, he said. This is only possible under specific circumstances and a legal purpose is needed, he warned. "Images are considered personal data in the U.K., and they are in general in most European countries," he added.

While drones might cause privacy issues, Europeans are slightly better protected against intrusions into their personal lives than U.S residents, because in Europe there is a baseline privacy law that the U.S. lacks, Lee said. This has supported various European law suits against Google Street View centered on privacy issues with the online image service.

For instance, in the Czech Republic, a court ruled that the camera on Street View cars should be lowered by 30 centimeters to prevent Google from looking over hedges into people's gardens or peeking through windows into private homes. "And if Google is forced to lower Street View cameras 30 centimeters in the Czech Republic, that might be a problem for UAS," Lee said.

Loek covers all things tech for the IDG News Service. Follow him on Twitter at @loekessers or email tips and comments to loek_essers@idg.com

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